New beautiful results on marine particle speciation, a challenge for the GEOTRACES community…

Science Highlights

3 December 2012

Advanced Light Source x-ray spectromicroscopy (XANES) allows a fine description of the marine Fe pool chemical speciation and mineralogy. This work describes diverse arrays of iron particles (20- 700 nm), showing impressive variations in the oxidation state and composition of these iron particles between the coasts of South Africa and Antarctica. Moreover, different iron pools are occurring in different frontal zones. Because particle speciation is directly linked to the element solubilities, these differences may affect the production of bioavailable dissolved iron.

Iron_particle_speciation

Source : Science (click on the image to view it larger)

Reference:

B. P. von der Heyden, A. N. Roychoudhury, T. N. Mtshali1, T. Tyliszczak, S. C. B. Myneni. (2012). Chemically and Geographically Distinct Solid-Phase Iron Pools in the Southern Ocean: Science 338 (6111): 1199-1201, DOI: 10.1126/science.1227504

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